Membership questions? Log in issues? Email info@brewersassociation.org

Author Topic: Glass Carboys and FG readings. How?  (Read 5001 times)

Offline pyrite

  • Brewer
  • ****
  • Posts: 443
  • Davis, CA
Glass Carboys and FG readings. How?
« on: July 17, 2011, 01:34:03 pm »
I used to take FG readings using a plastic wine thief, but since I use the wine thief for my barrel aged sours I don't dare.  Currently, I just guess-timate when the beer is done.  Fortunately , over the past couple years I've acquaint myself with the behaviour of the same 5 yeast strains, and keeping with the same brewing and fermentation methods I've had luck estimating when the beer has reached FG.  However, I'm curious to hear what approach my fellow brewers take with FG readings and fermenting in glass carboys?

If you don't get in over your head, how are you ever going to know how tall you are.

Offline maxieboy

  • Senior Brewmaster
  • ******
  • Posts: 1155
  • Mid MI
Re: Glass Carboys and FG readings. How?
« Reply #1 on: July 17, 2011, 01:44:20 pm »


You might have to shake it up and down a couple times to get enough of a sample for your hydrometer test tube. I've had mine for 11 yrs.
The only time I didn't check gravity before racking, it turned out I had a stuck fermentation. I checked before kegging and discovered it...
« Last Edit: July 17, 2011, 01:47:13 pm by maxieboy »
A dog can show you more honest affection with a flick of his tail than a man can gather through a lifetime of handshakes." Gene Hill

[47.7, 310.8] AR

AHA Member

Offline pyrite

  • Brewer
  • ****
  • Posts: 443
  • Davis, CA
Re: Glass Carboys and FG readings. How?
« Reply #2 on: July 17, 2011, 01:52:10 pm »
Thanks Maxieboy, I never thought of that....11yrs. that's exceptional.  I've owned 3 siphons in the past 5 years and unfortunately, they've all cracked and ended up breaking.  I switched over to the stainless steel racking crane.  I even tried taking samples using the ss-racking crane and was not able to ..  
« Last Edit: July 17, 2011, 01:55:01 pm by pyrite »
If you don't get in over your head, how are you ever going to know how tall you are.

Offline pyrite

  • Brewer
  • ****
  • Posts: 443
  • Davis, CA
Re: Glass Carboys and FG readings. How?
« Reply #3 on: July 17, 2011, 01:57:12 pm »


You might have to shake it up and down a couple times to get enough of a sample for your hydrometer test tube. I've had mine for 11 yrs.
The only time I didn't check gravity before racking, it turned out I had a stuck fermentation. I checked before kegging and discovered it...

Lucky you weren't bottling.
« Last Edit: July 17, 2011, 04:44:47 pm by pyrite »
If you don't get in over your head, how are you ever going to know how tall you are.

Offline maxieboy

  • Senior Brewmaster
  • ******
  • Posts: 1155
  • Mid MI
Re: Glass Carboys and FG readings. How?
« Reply #4 on: July 17, 2011, 02:00:22 pm »
You might be thinking of an Auto Siphon. The pic above is a thief. It has a type of one way valve on the end to trap your sample when you lift it out. Depending on the level of the beer in the carboy(low), you can shake it up and down a little to force more beer in it.
A dog can show you more honest affection with a flick of his tail than a man can gather through a lifetime of handshakes." Gene Hill

[47.7, 310.8] AR

AHA Member

Offline denny

  • Administrator
  • Retired with too much time on my hands
  • *****
  • Posts: 26849
  • Noti OR [1991.4, 287.6deg] AR
    • Dennybrew
Re: Glass Carboys and FG readings. How?
« Reply #5 on: July 17, 2011, 02:05:21 pm »
Sanitized turkey baster.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." - Bertrand Russell

Offline a10t2

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 4696
  • Ask me why I don't like Chico!
    • SeanTerrill.com
Re: Glass Carboys and FG readings. How?
« Reply #6 on: July 17, 2011, 02:07:44 pm »
Keeping separate plastics is probably good insurance when brewing sours. Why not just get a second wine thief? They're what, maybe $8?
Sent from my Microsoft Bob

Beer is like porn. You can buy it, but it's more fun to make your own.
Refractometer Calculator | Batch Sparging Calculator | Two Mile Brewing Co.

Offline pyrite

  • Brewer
  • ****
  • Posts: 443
  • Davis, CA
Re: Glass Carboys and FG readings. How?
« Reply #7 on: July 17, 2011, 03:52:43 pm »
Maxiboy, it looks just like an auto siphon.  My mistake.  Good idea.

Denny, turkey baster. Humm, not a bad idea.

a10t2, i thought of buying a second plastic wine thief, but was just wondering what everyone else uses.
If you don't get in over your head, how are you ever going to know how tall you are.

Offline roffenburger

  • Assistant Brewer
  • ***
  • Posts: 179
Re: Glass Carboys and FG readings. How?
« Reply #8 on: July 18, 2011, 04:35:44 pm »
Siphon, by mouth :o
Travis R.

Offline hopfenundmalz

  • Global Moderator
  • I must live here
  • *****
  • Posts: 10633
  • Milford, MI
Re: Glass Carboys and FG readings. How?
« Reply #9 on: July 18, 2011, 04:45:57 pm »
Sanitized turkey baster.

This is my SOP. 
Jeff Rankert
AHA Lifetime Member
BJCP National
Ann Arbor Brewers Guild
Home-brewing, not just a hobby, it is a lifestyle!

Offline Tristan

  • Assistant Brewer
  • ***
  • Posts: 105
  • Bastage Inc.
Re: Glass Carboys and FG readings. How?
« Reply #10 on: July 19, 2011, 06:57:59 am »
I use a long 10ML glass pipet with a pipet bulb then a few drops on the refractometer, then I run the numbers through the morebeer refractometer spreadsheet found at http://morebeer.com/public/beer/refractbeer.xls  It's more complicated than it needs to be but it's fast, easier to clean a little bulb/pipet and I like gadgets  ;D  Also, there is no plastic to scratch or cloud up.

The turkey baster is a killer idea.  I've seen stainless steel models at Bed Bath and Beyond.
« Last Edit: July 19, 2011, 06:59:40 am by Tristan »
Bastage Brewery:
Primary: ESB
Kegged: Baltic Porter|Blackened Doo Doo|CAP|German Pils|Infinity India Black Ale|Maibock|Munich Dunkel|Panty Raid APA|Schwartzbier|Turbo Coffee Porter
Next: Sweet Bidness Stout|Bastagewine

Offline a10t2

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 4696
  • Ask me why I don't like Chico!
    • SeanTerrill.com
Re: Glass Carboys and FG readings. How?
« Reply #11 on: July 19, 2011, 07:23:35 am »
I use a long 10ML glass pipet with a pipet bulb then a few drops on the refractometer, then I run the numbers through the morebeer refractometer spreadsheet found at http://morebeer.com/public/beer/refractbeer.xls

Good idea. Bad spreadsheet. ;D

seanterrill.com/2011/04/07/refractometer-fg-results/
Sent from my Microsoft Bob

Beer is like porn. You can buy it, but it's more fun to make your own.
Refractometer Calculator | Batch Sparging Calculator | Two Mile Brewing Co.

Offline Tristan

  • Assistant Brewer
  • ***
  • Posts: 105
  • Bastage Inc.
Re: Glass Carboys and FG readings. How?
« Reply #12 on: July 19, 2011, 07:32:36 am »
I use a long 10ML glass pipet with a pipet bulb then a few drops on the refractometer, then I run the numbers through the morebeer refractometer spreadsheet found at http://morebeer.com/public/beer/refractbeer.xls

Good idea. Bad spreadsheet. ;D

seanterrill.com/2011/04/07/refractometer-fg-results/

Killer spreadsheet!  Love it!  I just kegged a Kolsch on Sunday, morebeer spreadsheet reported FG at 1.004 and this new spreadsheet reports 1.007 - 1.008.  This is closer to taste perception when I sampled the Kolsch.
Bastage Brewery:
Primary: ESB
Kegged: Baltic Porter|Blackened Doo Doo|CAP|German Pils|Infinity India Black Ale|Maibock|Munich Dunkel|Panty Raid APA|Schwartzbier|Turbo Coffee Porter
Next: Sweet Bidness Stout|Bastagewine

Offline SpanishCastleAle

  • Brewer
  • ****
  • Posts: 272
Re: Glass Carboys and FG readings. How?
« Reply #13 on: July 19, 2011, 07:34:20 am »
I just catch (as opposed to 'take') a sample as I'm racking to the keg.  I've only had a couple stalled ferments and in each case they weren't going anywhere in the carboy. They had done all they were going to do and rousing, yeast energizer, etc weren't doing anything anyway.  So I just get it off the old yeast and if it is stuck I either pitch dry yeast or put it on a cake from a 'good' fermentation.  Either way, it needed to get out of the carboy so racking was the next step regardless of whether it was stuck or not.  So I don't measure first, I just rack it and measure the caught sample.  If I were bottling it'd be different.

narvin

  • Guest
Re: Glass Carboys and FG readings. How?
« Reply #14 on: July 19, 2011, 07:54:27 am »
I pull out my stopper with thermowell and let a drop or two fall on my refractometer... instant reading.


I also found the standard corrections to be off... over time I've settled on a rough linear correction of just adding 0.4 brix and using that reading in the ProMash calculator.  This adds anywhere from 0.002 to 0.004 points to the FG, which always read low for me using the refractometer estimate.  a10t2's graph looks like he's getting the same results in a more scientific way :-)